24-inch Television Tube (Dec, 1950)

24-inch Television Tubegets the once-over by two General Electric executives who wear eye protectors in case tube should shatter. The giant picture tube is here mounted on a glass-to-metal cone sealer. The smallest television tube made at G.E.’s Syracuse plant measures 8-1/2 inches. Limited production of king-size tube is to get under way soon.

Back in 1950 it was a big deal.
Got any technology in your life that’ll withstand scrutiny 60 years from now?

Noah says: October 17, 201010:22 am

I see 1950 had a lack of editors. Let me fix it for them.

This 24-inch Television Tube is viewed by two General Electric executives who wear eye protectors in case the tube shatters. The tube is mounted on a glass-to metal cone sealer. The smallest tube made by GE’s Syracuse plant is 8 1/2 inches. The 24 inch tube will enter limited production soon.

Jayessell says: October 17, 20101:17 pm

Weren’t there any large radar screens?
(I suppose THOSE used special phosphors.)
I hope it had plenty of XRay shielding!

Bob says: October 17, 20104:35 pm

In 1950, 17 inch screens were considered large, with 10″ sets still being sold. My folks bought a 12″ Motorola table model in 1950.

By the end of the 1950’s the 21 inch screen was more or less standard for B&W tv’s with sets available with screens up to 27″.

DuMont actually made a 30 inch tube in 1951 which was intended for use by institutions, taverns and schools.

The picture tube was perhaps the last receiving vacuum tube in regular use, until flat screens came into use. The rest of the TV or monitor would be solid state.

slim says: October 18, 20102:56 pm

This was about the time my folks bought their 8″ Emerson. The neighbors’ 12″ seemed really big. I can remember one of the neighbors had a magnifier. It was a plastic shell of a lens that you filled with water.

This was before people became aware of the X-Ray danger from color television sets.

Also, it looks as though you can see through the front face of the picture tube.

There was at least one early RCA picture tube which, although the glass on the front of the tube was curved, really had a flat screen. Because they didn’t have the technology, initially, to make a curved shadow mask plate, they put an assembly with a flat shadow mask and a flat glass plate with the phosphor dots on it inside the tube near the front.

One such tube was the 15GP22; it was a 15″ tube, the first production color CRT, but I think they later made other tubes that way as well in larger sizes.

Casandro says: October 18, 201010:55 pm

@Kosher Ham Actually you might be wrong. They have a strong battle with tubes inside of transmitters. Although manufacturers switched to solid state there years ago, those transmitters are often in use for decades. So if you have a country which still uses analog television, chances are the CRT-based television sets will be replaced quicker than the transmitters.

Kosher Ham says: October 19, 20109:32 am

I meant receiving tubes; not transmitting tubes. High power transmitters are or were easier to build using vacuum tubes as opposed to transistors and FETs. Even many of the kilowatt linears that hams use still use tubes, often imported from Russia.

JMyint says: October 19, 20102:23 pm

I don’t know of many solid state devices that can handle more than a 1000 watts, so high power applications are still the realm of vacuum tubes. Also I am not sure of the life expectancy of flat panel displays. I know from experience that CRTs can have a life expectancy of 30 years or better. Vacuum tubes of all types still make up a large portion of electronic production. All microwave ovens use a vacuum tube along with all x-ray devices.

This coming from a big fan of solid state.

Toronto says: October 19, 20106:25 pm

It’s not that hard to find SCRs that can handle 1500V and 1500A – that’s 2 1/4 million watts, give or take. Google seems to be telling me that 6 MegaVA silicon devices can be obtained.

But yeah, big tubes are cool (sometimes by water.)

JMyint says: October 20, 20109:13 am

Hmm. I did find a power thyristor, a T36A7KV, with a peak current rating of 3940 Amps and a peak voltage rating of 7000 volts, but not at the same time. It could however handle 3600 amps at 3.2 volts which is still a very respectable 10 kilowatts.

Kosher Ham says: October 20, 201011:13 am

High power thyristors have been used by power companies to convert DC to AC for years. Using DC for a long distance line eliminates the power factor problem with AC.

JMyint says: October 21, 201011:40 am

Yes but in the case of the power grid they are using thyristor stacks sometimes made of hundreds of thyristors. These thyristor stacks are frequently water or oil cooled to help reduced the heat build up.